In an era that emphasizes green technology, technologies relating to energy harvesting are becoming important. There is a need for finding new ways to save and reuse energy, while also making it affordable to do so. Energy harvesting refers to a process of capturing energy from external sources comprising, for example, sunlight, kinetic energy, wind, hydraulics, etc. Energy that is harvested from different sources is typically bountiful, and is present regardless of whether energy harvesting takes place. The harvested energy is typically converted to electricity to power electronic devices. Since energy harvesting does not depend on batteries or power sockets, the harvested energy is used as a power source in multiple different industries and portable electronic devices. For example, users can use the harvested energy to charge portable devices such as smartphones without the need to connect their smartphones to a power socket, thereby allowing the users to charge their smartphones on the go. Other electronic devices, for example, communication radios and flashlights can also use power from energy harvesting technologies in locations such as underground mines, deserts, and remote areas, where power sources are unavailable.
There are many conventional energy harvesting systems which generate electrical energy from mechanical motion, vibrations, etc. For example, a conventional energy harvesting system generates electrical energy from vibrations using piezoelectric materials. The piezoelectric materials create a charge when stressed. With these piezoelectric materials, each generator of 1 cubic centimeter in volume generates up to 0.5 milliwatts and can potentially be used to drive small autonomous devices such as pacemakers, wristwatches, or wireless sensors. Piezoelectric materials based energy harvester systems provide renewable electrical power from arbitrary, non-periodic vibrations. The non-periodic vibrations are obtained, for example, from traffic driving on bridges, machinery operating in industries, and humans moving their limbs. The conventional energy harvesting systems using piezoelectric materials generate insufficient power to power a standard portable electronic device. Further, the piezoelectric materials are expensive. Therefore, there is a need for an improved energy harvesting system that generates optimum electrical energy.
Hence, there is a long felt but unresolved need for an energy harvester system that converts a multiple degree of freedom pendulum motion into a rotational motion for generation of electrical energy to power portable electronic devices.